1. Field of the Invention
The invention is directed to scroll-type devices as well as to refrigeration systems and, in particular, to refrigeration systems utilizing scroll-type expansion devices.
2. Description of Related Art
Devices having scrolled features have been disclosed. For example, in a scroll compression process, an intermeshing of two spirals, or involutes, which interweave in an eccentric path, form a series of crescent shaped pockets as one scroll orbits relative to the other. Such techniques have been utilized in compressors wherein gas at low temperature and pressure enters at a periphery and is compressed as the pocket decreases in size, until it is discharged at a higher temperature and pressure.
Indeed, Armstrong et al., in U.S. Pat. No. 4,192,152, teach a scroll-type fluid displacement apparatus with peripheral drive. The orbiting scroll member is attached through radially-compliant linking means to eccentrics mounted on three equally spaced crankshafts to accommodate differential thermal expansion without the generation of any appreciable elastic forces to increase bearing loads. The apparatus may be staged and employed as a compressor or expander.
Haga et al., in U.S. Pat. No. 5,145,344, teach scroll-type fluid machinery with offset passage to the exhaust port. The machine has an orbiting scroll with involute wraps projecting axially on each of opposite sides, a pair of stationary scrolls each with involute wraps which mate with the wraps of the orbiting scroll, and a main shaft inserted in a central axis hole of the stationary scrolls for driving the orbiting scroll in orbital movement. The internal ends of the wraps of the stationary scrolls are extended inwardly to an outer peripheral wall of a land part where the central axis hole is formed. The stationary scroll wraps are extended about a half turn longer than the wrap of the orbiting scroll and the internal ends of the wraps are almost in contact end to end at a desired phase during the orbiting movement of the orbiting scroll.
McCullough, in U.S. Pat. No. 4,129,405, teaches a scroll-type liquid pump wherein recessed liquid transfer passage means are provided in the end plates of the scroll members. The transfer passage means may be inner passages within the scroll involutes, outer passages outside the scroll involutes or a combination of inner and outer passages. The passages are configured to be opened substantially immediately after the orbiting involute wrap has reached that point in its orbiting cycle to define three essentially completely sealed-off liquid zones. The passages remain open at least until the liquid passages between the wraps are sufficiently large to prevent any substantial pressure pulsations within the scroll liquid pump.
Hirano, in U.S. Pat. No. 5,330,463, teaches a scroll-type fluid machinery with reduced pressure biasing the stationary scroll. The scroll type fluid machinery has a stationary scroll and a revolving scroll with spiral elements set up at end plates thereof. The scrolls are engaged with each other, and a high pressure fluid chamber is formed on the outside of the end plate of the stationary scroll. A low pressure fluid chamber or an intermediate pressure fluid chamber is formed between the end plate of the stationary scroll and the high pressure fluid chamber. The pressure of a low pressure fluid or an intermediate pressure fluid acts on the outside of the end plate of the stationary scroll, and deformation of the end plate is prevented or reduced, and reliability of the fluid machinery may be improved.
Forni, in U.S. Pat. No. 5,637,942, teaches an aerodynamic drag reduction arrangement for use in a mechanical device that incorporates a high speed rotating element. The arrangement includes a boundary layer control member that defines a control surface. The control member is positioned adjacent the rotating element so as to optimize the clearance therebetween in order to effectively block axial flow and prevent radial pumping in order to minimize power consumption.
Forni, in U.S. Pat. No. 5,800,140, teaches a compact scroll fluid device. The device includes a pair of wrap support elements with one of the wrap support elements having an inner axial surface formed with an involute spiral recess and the other of the wrap support elements having an involute spiral wrap member projecting from an inner axial surface thereof. The spiral wrap member is received within the spiral recess while being relatively movable about an orbital path between the wrap support elements, radially inwardly of both inlet and outlet zones associated with the scroll fluid device and radially outwardly of an orbit center of the device.
Yamanaka et al., in U.S. Pat. No. 6,321,564 and No. 6,543,238, teach a refrigerant cycle system with expansion energy recovery. The refrigerant of the system is compressed in a first compressor, is cooled and condensed in a radiator, and refrigerant from the radiator branches into main-flow refrigerant and supplementary-flow refrigerant. The main-flow refrigerant is decompressed in an expansion unit while expansion energy of the main-flow refrigerant is converted to mechanical energy. Thus the enthalpy of the main-flow refrigerant is reduced along an isentropic curve. Therefore, even when the pressure within the evaporator increases, refrigerating effect is prevented from being greatly reduced in the refrigerant cycle system. Further, refrigerant flowing into the radiator is compressed using the converted mechanical energy. Thus, coefficient of performance of the refrigeration cycle is improved.
Masayuki et al., in Japanese Patent No. 2004-257303, teach a scroll expansion machine and refrigerating air conditioner.